KR20090081343A - Inspection method and program storage medium storing the method - Google Patents

Abstract

An inspecting method and a program recording medium recording the same are provided to repeatedly contact a probe with an object to be inspected without the damage to an electrode pad of the object to be inspected in order to increase reliability. An inspecting method uses a plurality of needle marks of a probe and compensates the contact location of a plurality of electrode pads and probes. A method for compensating the contact location comprises the following steps of: taking a picture of electrode pads to detect needle marks formed on the electrode pads and to obtain a first image(S1); producing the spatial deviation of the each needle mark by using the first image and compensating the contact location of the probes and electrode pads to coincide with the center of the electrode pads by using the needle mark locations and the spatial deviation(S2).

Description

Inspection method and program recording medium which recorded this inspection method {INSPECTION METHOD AND PROGRAM STORAGE MEDIUM STORING THE METHOD}

The present invention relates to an inspection method for performing electrical characteristic inspection of an inspection object such as a semiconductor wafer using a probe card, and a program recording medium recording the inspection method. A program recording medium having recorded this inspection method.

The inspection apparatus includes a loader chamber and a prober chamber adjacent to each other. The loader chamber executes pre-alignment of the semiconductor wafer during the transfer of the semiconductor wafer, the mounting unit for mounting the inspected object (for example, the semiconductor wafer) in units of cassettes, the semiconductor wafer conveying mechanism for conveying the semiconductor wafers one by one from the cassette, and the semiconductor wafer during the conveyance. A sub chuck is provided. The prober chamber is a temperature-controllable and movable main chuck on which a semiconductor wafer carried by a wafer transfer mechanism of a loader chamber is mounted, a probe card disposed above the main chuck, a plurality of probes of the probe card, and a semiconductor on the main chuck. An alignment mechanism for performing alignment of the plurality of electrode pads of each of the plurality of devices formed on the wafer, and after performing the alignment of the electrode pad and the probe of the semiconductor wafer via the alignment mechanism, the semiconductor wafer is predetermined through the main chuck. It is set to the temperature of and it is comprised so that the electrical property test of a test subject may be performed at this set temperature.

In the case of performing the electrical property inspection on each device of the semiconductor wafer, the imaging device (for example, a CCD camera) of the alignment mechanism is used to image a device including a plurality of electrode pads formed on the semiconductor wafer and simultaneously probe The needle tips of the plurality of probes of the card are imaged, and the plurality of electrode pads and the plurality of probes are aligned based on the positional information of both of them. Thereafter, the semiconductor wafer is raised by a predetermined dimension through the mounting table and overdriven to electrically contact the plurality of electrode pads and the plurality of probes to thereby conduct electrical property inspection of the device. However, due to the high integration of the devices, the electrode pads are rapidly miniaturized and the number of pads increases, and the number of probes of the probe card also increases rapidly. For this reason, detection of a probe by a CCD camera at the time of alignment becomes difficult.

By the way, while repeating the inspection, the needle tip position fluctuates due to deformation of the plurality of probes or the like. When the plurality of probes are deformed and the needle tip position gradually increases, conduction of the plurality of probes and the plurality of electrode pads may not be taken even when the semiconductor wafer is overdriven. Therefore, Patent Document 1 compares an overdrive amount with a camera by detecting a needle trace formed on an actual pad. When the needle tip position becomes high, the main chuck is raised based on a comparison result to always obtain an appropriate overdrive amount. It is described about a prober capable of providing a stable inspection.

Patent Literature 2 obtains positional shift information by a contact state between a virtual pad (design pad) and a probe, and not only virtually monitors the actual contact state between the pad and the probe, but also according to the result obtained in the contact state. The inspection apparatus which can correct | amend to an optimal contact state is described.

In Patent Literature 3, the position of the needle and the position of the electrode are respectively detected, and a needle mark indicating the position of the needle mark and the position of the needle mark is displayed on the display device, the positional deviation of the needle mark is calculated, and the operator displays an image. A prober that corrects the position of the needle mark, calculates the positional deviation of the needle mark, and corrects the shift amount calculation correction value of the semiconductor wafer based on the calculated deviation.

Moreover, patent document 4 has described about the test | inspection apparatus which calculates the position shift amount of the probe which contacts next according to the needle trace formed in the electrode pad. Moreover, in this inspection apparatus, after a probe contacts the electrode pad in which the existing needle trace was formed, the post-contact image which shows the area | region containing the electrode pad is acquired, and then compares it with the image before contact, The technique of acquiring the needle trace of a figure, correcting a position shift amount using the latest needle mark, and using the position shift amount for the following inspection is described.

[Patent Document 1] Japanese Patent Publication No. Pyeongseong 5-036765

[Patent Document 2] Japanese Patent Publication No. Pyeongseong 7-288270

[Patent Document 3] Japanese Patent Laid-Open No. 2006-339196

[Patent Document 4] Japanese Patent Laid-Open No. 2006-278381

However, all of the prior arts can correct the positional shifts of the plurality of electrode pads and the plurality of probes by obtaining the positional shift amounts of the plurality of electrodes and the plurality of probes. There is no guarantee that the electrode pad will be reliably contacted, and even if it is in contact, if the new needle trace repeatedly contacts the existing needle trace, the electrode pad may be damaged, and further, the device may be damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and even when the electrode pad is miniaturized and thinned, the needle pad formed on the electrode pad can be used to accurately and repeatedly contact the electrode pad of the inspected object with a probe to perform a highly reliable test. It is an object of the present invention to provide an inspection method that can be used and a program recording medium that records the inspection method. In addition, the present invention, even in the case of miniaturization and thinning of the electrode pad, by using the needle marks formed on the electrode pad, the inspection can be carried out with high accuracy and repeatable contact with the probe without damaging the electrode pad of the subject under test It aims at providing the method and the program recording medium which recorded this inspection method together.

In the inspection method according to claim 1 of the present invention, a plurality of electrode pads of a test target mounted on a mounting target and a plurality of probes of a probe card disposed above the mounting table are electrically contacted to inspect the electrical characteristics of the test target. A test method for performing a test, wherein the contact points of the plurality of electrode pads and the plurality of probes are corrected in preparation for the current inspection by using the needle marks of the plurality of probes formed on each of the plurality of electrode pads in a previous test. And correcting the contact positions of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, wherein the plurality of electrodes are used to detect the needle marks formed on each of the plurality of electrode pads. A first process of imaging a pad to obtain a first image, and each of the plurality of electrode pads using the first image The second step of obtaining the positional displacement amount of the center and the center of each of the needle marks in these electrode pads; and the contact positions of the plurality of probes of the plurality of probes used for the inspection. And a third step of correcting each center of the plurality of electrode pads by using the positions of the plurality of needle marks and the respective amount of positional displacements, and a plurality of points used for the inspection after the corrections in the third step. A fourth step of forming a new needle trace on each of the electrode pads by contacting a probe with the plurality of electrode pads; and a fifth step of capturing a plurality of electrode pads on which the new needle marks are formed, respectively, to obtain a second image. And the contact of each of the plurality of probes based on the size of the plurality of electrode pads and the center of a new needle mark in each electrode pad. That the said regions having a sixth step to obtain in each electrode pad is characterized.

In addition, the inspection method according to claim 2 of the present invention electrically contacts a plurality of electrode pads of a test target mounted on a mounting target with a plurality of probes of a probe card disposed above the mounting table, and thereby the electrical characteristics of the test target. An inspection method for performing an inspection, wherein a contact position of the plurality of electrode pads and the plurality of probes is prepared in preparation for the present inspection by using the needle marks of the plurality of probes formed on each of the plurality of electrode pads in a previous inspection. And correcting the contact positions of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, wherein the plurality of electrode pads are configured to detect the needle marks formed on each of the plurality of electrode pads. And a plurality of electrode pads using a first step of imaging an electrode pad of the device to obtain a first image and using the first image. A second step of obtaining a positional shift amount of the center of each of the centers and the centers of the respective needle marks in these electrode pads; and the contact of the plurality of probes of the plurality of probes used for the inspection. A third step of correcting the position to the center of the plurality of electrode pads by using the positions of the plurality of needle marks and respective positional displacement amounts, and used for the inspection after the correction in the third step. A fourth step of forming a new needle trace on each of the electrode pads by bringing a plurality of probes into contact with the plurality of electrode pads; and obtaining a second image by imaging a plurality of electrode pads on which the new needle marks are formed, respectively. Step 5, the first image is compared with the second image to extract an image of a new needle mark of each of the plurality of electrode pads, and the plurality of electrodes The center displacement of each center and the center displacement of each of the new needle marks in these electrode pads, and using the positional displacement amount, a predetermined position of contact to be contacted by the plurality of probes in the next inspection; These contact scheduled positions are compared with the blank areas without the needle marks of the second image. When the contact scheduled positions are included in the respective blank areas, the contact scheduled positions are arranged in the respective blank areas and the respective centers of gravity are placed. And a seventh step of correcting the contact position of each of the plurality of probes with the center of the contact scheduled position arranged in the respective blank areas.

In addition, the test method according to claim 3 of the present invention electrically contacts a plurality of electrode pads of a test target mounted on a mounting target with a plurality of probes of a probe card disposed above the mounting table, and thereby the electrical characteristics of the test target. An inspection method for performing an inspection, wherein a contact position of the plurality of electrode pads and the plurality of probes is prepared in preparation for the present inspection by using the needle marks of the plurality of probes formed on each of the plurality of electrode pads in a previous inspection. And correcting the contact positions of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, wherein the plurality of electrode pads are configured to detect the needle marks formed on each of the plurality of electrode pads. And a plurality of electrode pads using a first step of imaging an electrode pad of the device to obtain a first image and using the first image. The second process of obtaining the position shift amount of the center of each and the center of each said needle trace in these electrode pads, and the contact position with respect to the said some electrode of the some probe used for the said inspection, A third step of correcting the center of the plurality of electrode pads by using the position of the needle trace and the respective amount of positional displacement; a plurality of probes and the plurality of probes used for the inspection after the correction in the third step; A fourth step of forming new needle marks in each of the plurality of electrode pads by contacting the electrode pads; a fifth step of imaging a plurality of electrode pads in which the new needle marks are formed, respectively, to obtain a second image; Contactable area of each of the plurality of probes based on the size of the electrode pad and the center of the new needle mark on each electrode pad A sixth step obtained in each of the electrode pads, a seventh step of determining whether each of the plurality of contactable areas is included in the plurality of electrode pads of the second image, and each of the plurality of contactable areas When included in the plurality of electrode pads, an eighth step of extracting images of new needle marks in the plurality of electrode pads based on the first image and the second image, the center of each of the plurality of electrode pads, and these electrodes The positional displacement amount of each center of the new needle trace in the pad is obtained, and the positional displacement amount of the plurality of probes is to be contacted in the next inspection by using the positional displacement amount. Each of the electrode pads of the electrode pads of the electrode pads of the electrode pads of the electrode pads was compared with each other. When included in the each blank area it will, characterized in that the arrangement of the contact in a predetermined position each blank area and a ninth step to obtain the respective centers of (重心) a contact position of said plurality of probes, respectively.

In addition, the inspection method according to claim 4 of the present invention electrically contacts a plurality of electrode pads of an inspected object mounted on a mounting object with a plurality of probes of a probe card disposed above the mounting table, thereby providing electrical characteristics of the inspected object. An inspection method for performing an inspection, wherein a contact position of the plurality of electrode pads and the plurality of probes is prepared in preparation for the present inspection by using the needle marks of the plurality of probes formed on each of the plurality of electrode pads in a previous inspection. And correcting the contact positions of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, wherein the plurality of electrode pads are configured to detect the needle marks formed on each of the plurality of electrode pads. A plurality of electrode pads each using a first step of capturing an electrode pad of the first electrode to obtain a first image, and using the first image A second step of obtaining the positional displacement amount of the center of each center and the center of gravity of each of the needle marks in these electrode pads; and the plurality of probes of the plurality of probes used for the inspection. A third step of adjusting the contact position to the center of the plurality of electrode pads using the positions of the plurality of needle marks and the respective positional displacement amounts, and used for the inspection after the correction in the third step; A fourth process of forming new needle marks on the plurality of electrode pads by contacting the plurality of probes with the plurality of electrode pads, and obtaining a second image by imaging the plurality of electrode pads on which the new needle marks are formed, respectively. Comparing the fifth step with the first image and the second image, the images of the plurality of new needle marks are extracted, respectively, and the centers of the plurality of extracted images ( A sixth step of obtaining a predetermined contact position at which the plurality of probes makes contact in the next inspection based on the same procedure as in the first to third processes based on the center of the electrode pad and each of the electrode pads; When the plurality of extracted images respectively disposed at the predetermined positions overlap each other with the existing needle marks, the respective contact scheduled positions are moved to the shortest distance at the position where the overlap is minimized to correct the contact scheduled positions. It is characterized by including the 7B process.

In addition, the test method according to claim 5 of the present invention electrically contacts a plurality of electrode pads of a test target mounted on a mounting target with a plurality of probes of a probe card disposed above the mounting table, and thereby the electrical characteristics of the test target. An inspection method for performing an inspection of a plurality of probes, comprising: contacting the plurality of electrode pads with a plurality of probes in preparation for the current inspection by using needle marks of the plurality of probes formed on each of the plurality of electrode pads in a previous inspection. And correcting the position, and correcting the contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, to detect the needle marks formed on each of the plurality of electrode pads. A first process of imaging a plurality of electrode pads to obtain a first image, and the plurality of electrode pads using the first image. A second step of obtaining a positional shift amount of the center of each of the centers and the centers of the respective needle marks in these electrode pads; and the contact of the plurality of probes of the plurality of probes used for the inspection. A third step of correcting the position to the center of the plurality of electrode pads by using the positions of the plurality of needle marks and respective positional displacement amounts, and used for the inspection after the correction in the third step. A fourth step of forming a new needle trace on each of the electrode pads by bringing a plurality of probes into contact with the plurality of electrode pads; and obtaining a second image by imaging a plurality of electrode pads on which the new needle marks are formed, respectively. Step 5, the first image and the second image are compared to extract images of the plurality of new needle marks, respectively, and the centers of the plurality of extracted images ( A sixth step of obtaining a predetermined contact position at which the plurality of probes contact each other in the next inspection in the same procedure as the first to third processes based on the center of the electrode pad and the respective electrode pads; and the second image In each of the plurality of electrode pads, a Voronoi DIAGRAM is created based on the existing plurality of needle marks, and the Voronoi closest to the center of each of the extracted images disposed at the plurality of contact scheduled positions. And a seventh C step of correcting each of the contact scheduled positions by moving the shortest distance up to the boundary line.

Moreover, the test method of Claim 6 of this invention is the invention of any one of Claims 1-5, The said new needle trace is formed using the to-be-tested object previously set to predetermined temperature, It is characterized by the above-mentioned.

Moreover, in the inspection method of Claim 7 of this invention, in the invention of any one of Claims 1-5, the position shift amount calculated | required in the said 2nd process is the center of the said some electrode pad, and the said some electrode It is characterized in that it is obtained by the least square method using the center of the needle marks formed on each.

Moreover, in the inspection method of Claim 8 of this invention, in the invention of Claim 1 or Claim 3, the range of the x coordinate value of the contactable area calculated | required by the said 6th process is made into the origin of the center of the said some electrode pad. A corrected x coordinate value obtained by adding half of the width in the x direction of the new needle trace to an x coordinate value of an edge on the negative side of the electrode pad, and the new needle trace having a maximum x coordinate value to the corrected x coordinate value. The new needle trace having the larger one of the sum of the x-coordinates of the center position as the minimum x-coordinate and the x-coordinate of the edge on the positive side of the electrode pad and the minimum x-coordinate on the edge. Obtaining the smaller one of the sum of the x coordinates of the center position of as the largest x coordinate, and obtaining the range of the y coordinates of the contactable region in the same manner as the range of the x coordinate values. It is characterized by.

The program recording medium according to claim 9 of the present invention drives a computer to electrically contact a plurality of electrode pads of an object to be mounted on a mounting object and a plurality of probes of a probe card disposed above the mounting table. An inspection method for inspecting electrical characteristics of the inspected object, wherein the plurality of electrode pads and the plurality of electrode pads are prepared in preparation for the current inspection by using needle marks of the plurality of probes formed on each of the plurality of electrode pads in a previous inspection. A program recording medium having recorded thereon a program for executing a test method including a step of correcting contact positions of a plurality of probes, wherein the needle marks are used to correct the contact positions of the plurality of electrode pads and the plurality of probes. The program drives the computer, and the inspection room according to any one of claims 1 to 5. It is characterized by executing the law.

According to the present invention, even when the electrode pad is miniaturized and thinned, an inspection method capable of performing highly reliable inspection by repeatedly contacting the electrode pad of the inspected object with a probe with high accuracy by using a needle trace formed on the electrode pad, and this inspection It is an object of the present invention to provide a program recording medium recording a method. According to the present invention, even when the electrode pad is miniaturized and thinned, by using the needle marks formed on the electrode pad, it is possible to perform highly reliable inspection by repeatedly contacting the probe with high accuracy without damaging the electrode pad of the inspected object. It aims at providing both the test method which exists and the program recording medium which recorded this test method.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of the test | inspection apparatus and test method of this invention is described, referring FIGS. In each figure, FIG. 1 is a block diagram showing the structure of an inspection apparatus used for carrying out one embodiment of the method of the present invention, and FIG. 2 shows one embodiment of the inspection method of the present invention using the inspection apparatus shown in FIG. FIG. 3 is a flowchart showing a part of the flowchart shown in FIG. 1 in more detail, and FIGS. 4A and 4B show the amount of positional shift based on the needle traces of the probes in the electrode pads of the device, respectively. (A) is a diagram showing spherical needle marks, (b) is a diagram showing needle traces of an ideal probe, and (a) to (c) of FIG. 5 are each on the electrode pad of the second image. A plan view showing a process of extracting a new needle mark using an existing needle mark of the electrode pad of the first image from the needle mark, and FIGS. 6 (a) and 6 (b) respectively show another embodiment of the inspection method of the present invention.7A and 7B are plan views showing the contactable regions of the probes in the electrode pads, and FIGS. 8A, 8B and 8C are respectively shown in the electrode pads. 9A to 9C show the relationship between the contactable area of the probe and the arrangement area of the probe to be allocated in the next inspection. 10 (a) and 10 (b) are plan views illustrating the overlapping state of the contact scheduled position of the probe and the existing needle marks, respectively, and FIGS. 11 (a) to (d). Is a plan view for explaining a state in which a probe scheduled position of the probe overlaps with a conventional needle trace, and FIGS. 12A and 12B illustrate a method of correcting by shifting a probe scheduled position to an optimal position, respectively. 13 is a plan view for optimally positioning the contact position of the probe FIG. 14 is a plan view illustrating a method of correcting the contact position by correcting it by moving to an optimal position when the contact position of the probe is caught by the passivation layer, and FIG. (a) and (b) are each a plan view for explaining another method of moving and correcting a contact scheduled position of a probe to an optimum position, respectively.

1st Embodiment

First, the inspection apparatus provided with the program recording medium which recorded the inspection method of this invention is demonstrated. For example, as shown in FIG. 1, the inspection apparatus 10 includes a movable mounting table 11 that mounts a semiconductor wafer W as an object to be inspected and incorporates a temperature adjusting mechanism, and an upper side of the mounting table 11. An alignment mechanism 13 for performing alignment of the probe card 12 disposed on the substrate, the plurality of probes 12A of the probe card 12, and the semiconductor wafer W on the mounting table 11, and the alignment mechanism 13 A display device having an imaging means (e.g., a CCD camera) 13A constituting a display device, a display screen 14 for displaying an image picked up by the CCD camera 13A, and a computer for controlling these components. A plurality of probes 12A of the semiconductor wafer W and the probe card 12 on the mounting table 11 are provided by the alignment mechanism 13 under the control of the control device 15, which is mainly composed of the control device 15. After the alignment is performed, the plurality of probes 12A and the semiconductor wafer The electrical contact of the W is configured to perform an electrical characteristic test of the semiconductor wafer W.

In addition, the inspection apparatus 10 includes an input unit 16 such as a display screen 14 and a keyboard as shown in FIG. 1, and the input unit 16 performs various inspection conditions for executing the inspection method of the present invention. A variety of programs can be executed by operating menus or icons displayed on the display screen 14.

As shown in FIG. 1, the mounting table 11 includes a drive mechanism 11A and a detector (for example, an encoder) 11B, and moves in the X, Y, Z, and θ directions through the drive mechanism 11A. In addition, it is configured to detect the movement amount via the encoder 11B. The drive mechanism 11A includes, for example, a horizontal drive mechanism (not shown) mainly driven by a motor and a ball screw, and a lift drive built in the mount 11 for driving the XY table on which the mount 11 is arranged. A mechanism and a θ drive mechanism for rotating the mounting table 11 in the θ direction are provided. The encoder 11B detects the movement distance of the XY table in the X and Y directions, respectively, via the rotational speed of the motor, and transmits each detection signal to the control device 15. The control device 15 controls the drive mechanism 11A based on the signal from the encoder 11B, thereby controlling the amount of movement in the X and Y directions of the mounting table 11.

The alignment mechanism 13 is equipped with the CCD camera 13A and the alignment bridge 13B as mentioned above. As shown in FIG. 1, the CCD camera 13A is attached to the alignment bridge 13B. The CCD camera 13A has a zoom function and picks up the semiconductor wafer W at a predetermined magnification.

The CCD camera 13A enters the probe center from the back of the prober via the alignment bridge 13B and is located between the probe card 12 and the mounting table 11, where the mounting table 11 is in the X and Y directions. While moving to, the semiconductor wafer W is imaged at a predetermined magnification from the top, an image pickup signal is transmitted to the control device 15, and an image of the semiconductor wafer is displayed on the display screen 14 via the control device 15. Display.

The control unit 15 includes a central processing unit 15A, a program storage unit 15B in which various programs including a program for executing the inspection method of the present invention are stored, and a storage unit 15C which stores various data. And an image processing unit 15D for image processing the image pickup signal from the CCD camera 13A, an image storage unit 15E for storing the image signal from the image processing unit 15D as image data, and the image signal. On the display screen 14, a display control unit 15F for displaying a captured image or the like is provided, and a signal is transmitted and received between the central processing unit 15A, the program storage unit 15B, and the storage unit 15C. Various components of the inspection apparatus 10 are controlled.

An input unit 16 is connected to the central arithmetic unit 15A, and various data signals inputted from the input unit 16 are processed by the central arithmetic unit 15A and stored in the storage unit 15C. In the present embodiment, a program for executing the inspection method of the present invention is stored in the program storage unit 15B, and a captured image, an operation panel, and the like are displayed on the display screen 14. As described later, the operation panel has a function of moving the CCD camera 13A prior to alignment or registering image information such as position data of the probe card 12. That is, the CCD camera 13A is configured to move in the X and Y directions by pressing the horizontal shift operation key of the operation panel and to move in the Z direction by pressing the vertical shift operation key of the operation panel.

The image storage unit 15E and the display control unit 15F are connected to the central processing unit 15A, and the captured image by the CCD camera 13A is passed through the central processing unit 15A and the display control unit 15F. It displays on the display screen 14, respectively. In addition to the current captured image by the CCD camera 13A, the image storage unit 15E can store past captured images, processed images, and the like.

Programs such as the inspection method of the present invention are stored in the program storage section 15B via various recording media. In addition, these programs can also be downloaded to various inspection apparatuses by a communication medium. In this embodiment, the program of the inspection method stored in the program storage unit 15B is executed.

Next, one embodiment of the inspection method of the present invention will be described with reference to FIGS. 2 to 6. The inspection method of the present embodiment uses an existing needle trace (hereinafter, referred to as "needle needle") formed on the electrode pad in the last inspection by using the precision inspection function of the needle trace attached to the inspection apparatus 10. After correcting the contact positions of the plurality of probes before the current inspection, the plurality of probes are brought into contact with the plurality of electrode pads to form new needle marks (hereinafter referred to as "new needle marks"), and the new needle marks It is characterized in that the next optimum contact position is obtained. Therefore, the semiconductor wafer W used in the inspection method of this embodiment has already been subjected to at least one electrical property inspection, and at least one probe needle trace is formed on each of the electrode pads of the plurality of devices. In this inspection, the same probe card used in the previous inspection is used.

In the inspection method of this embodiment, the contact position of the some probe 12A is correct | amended according to the flowchart shown in FIG. 2, for example. Hereinafter, the case where high temperature inspection of the semiconductor wafer W is performed is demonstrated.

That is, as shown in FIG. 2, the device D which has the electrode pad P (refer FIG. 4) with a spherical needle F before this time contact is image | photographed with the CCD camera 13A (step S1). Specifically, in the inspection apparatus 10, under the control of the controller 15, the semiconductor wafer W is mounted on the mounting table 11 in the prober chamber from the loader chamber by the wafer transfer mechanism, and at the same time, the temperature adjusting mechanism is used. Thus, the semiconductor wafer W is heated to a predetermined temperature (for example, 150 ° C.). In the meantime, the alignment bridge 13B advances to the probe center from the back of the probe chamber and stops.

Thereafter, while the mounting table 11 moves in the X and Y directions, the CCD camera 13A of the alignment bridge 13B finds the predetermined device D in the semiconductor wafer W at low magnification, and the device D is the CCD camera. When it reaches just below 13A, CCD camera 13A becomes high magnification and image | photographs the predetermined device D (step S1). The CCD camera 13A transmits an imaging signal to the image processing unit 15D, and here, for example, performs a binarization process of the captured image based on the imaging signal based on a predetermined threshold value, and then the image storage unit 15E. ) Is stored as the first image. In addition, the display control unit 15F of the control device 15 operates to display the first image of the image storage unit 15E on the display screen 14 as shown in FIG. 1.

The enlarged 1st image shown in FIG. 1 is an image shown to FIG. 4A. In FIG. 4A, the image of the device D is displayed as a binarized image, the electrode pad P is white, and another portion including the spherical needle F is displayed in black. The broken line orthogonal to each electrode pad P passes through the intermediate point of each side of each electrode pad P, and the intersection point in the electrode pad P of each broken line becomes origin zero of the xy coordinate of electrode pad P. FIG. In addition, the cross mark of the old needle trace F has shown the center of gravity.

4B shows the needle traces Fi of an ideal probe card manufactured as designed. In the ideal probe card, as shown in Fig. 4B, when a plurality of probes contact the electrode pad P, the center of the needle trace Fi coincides with the origin O of the corresponding electrode pad P. FIG. By the way, the actual probe card 12 contains a manufacturing error etc., As mentioned above, the needle tip position of each probe 12A deviates a little from the origin of the electrode pad P in the x and y directions.

Therefore, in this inspection, the contact position is corrected by using the needle needle F of the electrode pad P of the first image and the ideal probe card needle trace Fi (step S2). In order to perform this correction, it is necessary to determine the positional displacement amounts of the spherical needle marks F of the plurality of probes 12A and the ideal needle marks Fi. Therefore, as shown in Fig. 4A, the xy coordinate of the center position of the spherical needle F is defined as (xi, yi), and as shown in Fig. 4B, xy of the center of the ideal needle marks Fi is shown. The coordinates are defined as (ui, vi). Then, it is assumed that the contact position of the probe card 12 is corrected by moving by the error amount (x, y) in the x direction and the y direction of the semiconductor wafer W, respectively. The error Lt can be obtained by the following equation. However, it is assumed that there are n electrode pads P. In addition, in FIG.4 (a), (b), the xy coordinate value of the center of the needle trace Fi and F adhering to each electrode pad D is written adjacent to each electrode pad P. As shown to FIG.

Lt = Σ ((xi- (x + ui)) ² + (yi- (y + vi)) ² )... Equation 1

Here, what is necessary is just to find (x, y) whose error Lt becomes a minimum value. Since the error Lt is a quadratic function of x and y, there is always a minimum value. Therefore, this local minimum can be obtained by partial derivative of Lt by x and y. Partial partial differentiation of Lt into x and y gives the following equations 2A and 2B.

dLt / dx = 2nx + 2 (Σ (ui-xi)) = 0. Equation 2A

dLt / dy = 2ny + 2 (Σ (vi-yi)) = 0. Formula 2B

Formulas 3A and 3B shown below are obtained from Expressions 2A and 2B. As evident from these equations, since (ui-xi) and (vi-yi) are shift amounts of the old needle marks F and the ideal needle marks Fi, respectively, the correction amount is the old needle marks F of the actual plurality of probes 12A. It becomes an average value of the shift amount from the center of each electrode pad of the center of. In order to make the some probe 12A contact the center of each electrode pad P in this test | inspection, what is necessary is just to correct the semiconductor wafer W to the x direction and the y direction by the average value of the shift amount of the center of the spherical needle trace F. FIG. Therefore, by using this average value as a correction amount of position shift, the center of the old needle trace F can be corrected in this inspection. However, in order to correct the position shift, the semiconductor wafer W is moved in the reverse direction, so that the correction amounts are (-x, -y).

x = (Σ (ui-xi)) / n... Formula 3A

y = (Σ (vi-yi)) / n... Formula 3B

In step S2, after obtaining the correction amount of the contact position of the probe card 12, the mounting table 11 moves by the correction amount in the x direction and the y direction, respectively, and the contact positions of the plurality of electrode pads P and the plurality of probes 12A. Calibrate As a result, the alignment between the semiconductor wafer W and the probe card 12 is completed. In this alignment, since all of the plurality of probes 12A are executed, alignment with high precision can be executed. After the completion of the alignment, the mounting table 11 is raised to contact the semiconductor wafer W, which has already been heated to 150 ° C., and the preheated probe card 12, and the mounting table 11 is overdriven to provide a plurality of electrodes of the device D. The pad P and the plurality of probes 12A are electrically contacted to form new needle marks (step S3). For example, as shown in Fig. 5 (a), an arbitrary needle pad F is formed on an arbitrary electrode pad P of the first image, and the corresponding probe 12A of the preheated probe card 12 is shown in Figs. As shown in Fig. 5B, new needle marks, i.e., new needle marks Fn, are formed.

Subsequently, under the control of the controller 15, the mounting table 11 is lowered to a predetermined position and the semiconductor wafer W is moved away from the probe card 12, and then the alignment bridge 13B advances to the probe center and the CCD camera. Electrode pad P is imaged by 13A (step S4). The CCD camera 13A transmits an image pickup signal to the image processing unit 15D, and after image processing to obtain a binary image, stores this binary image as a second image in the image storage unit 15E.

Subsequently, under the control of the control device 15, the display screen 14 displays a device D having a plurality of electrode pads P having the new needle marks Fn formed thereon as a second image. The new needle marks Fn formed on the plurality of electrode pads P of the device D are used to correct the contact positions of the plurality of electrode pads P and the plurality of probes 12A in preparation for the next high temperature inspection. In the same manner as in Step 2, the xy coordinate value of the center of the new needle trace Fn and the xy coordinate value of the center of the electrode pad P are applied to the equations 3A and 3B to obtain the correction amount required for the next high temperature inspection (step S5). ).

In the present embodiment, not only the correction amount required for the next high temperature inspection is obtained, but also the contactable area S of the probe 12A in the electrode pad P is obtained according to the flowchart shown in FIG. The probe 12A determines whether there is an empty area that can be contacted without overlapping with the existing needle trace F, and if there is such an empty region, the amount of correction of the probe 12A that forms needle marks in the empty area. Obtain

A method of obtaining the contactable area S of the probe 12A will be described with reference to FIG. 6. Fig. 6A shows a state where a vertical probe is used as the probe, the needle tip of the vertical probe is displaced only in the x direction, and there is no position misalignment in the y direction. When there is a positional shift in the y direction, it can be handled as in the x direction. Here, a case in which circular needle marks are formed on the electrode pad by using a vertical needle to simplify the method of obtaining the contactable area S will be described. However, in the cantilever-type probe 12A, as shown in FIG. Although needle marks are formed, the principle remains unchanged even in this case.

The needle marks F of the electrode pads P are Δx1, Δx2,... It is assumed that there is a deviation in position shift from the center (ideal needle trace) of the electrode pad P only at Δxn. In this description, Δ is omitted. From the plurality of electrode pads P, X _min = min (x1, x2, ... xn) and the center of the needle trace F having the smallest position shift in the x direction and the center of the needle trace F having the largest position displacement in the x direction. _max = max (x1, x2, ... xn).

The minimum value C _{min in the} x direction and the maximum value C _max in the x direction of the contactable region S of the vertical probe can be obtained by the following expressions 4A and 4B. However, in these formulas, w1 is the width dimension of the electrode pad P, and w2 means the diameter of a vertical probe. Equations 4A and 4B below are expressions in the case where the width w1 of the electrode pad P and the diameter w2 of the vertical probe are both assumed to be constant values. The contactable area S of the vertical probe obtained by equations 4A and 4B is a rectangular area indicated by hatched in Fig. 6B. Adding and subtracting w2 / 2 in equations 4A and 4B takes into account the radius of the vertical probe and prevents the vertical probe from protruding from the passivation edge surrounding the electrode pad P.

C _min = max (-w 1/2 + w 2/2, -w 1/2 + w 2/2 + x _max )... Equation 4A

C _max = min (w 1/2 -w 2/2, w 1/2/2 w 2/2 + x _min ). Formula 4B

Equations 4A and 4B assume that the size of the electrode pad P and the size of the needle trace F of the probe 12A are the same. When the size of the electrode pad P and the size of the needle trace F of the probe 12A are different from each other, the following equations 4Ci and 4Di are established as equations corresponding to the above equations 4A and 4B. In the following equations 4Ci and 4Di, the width dimension of the i-th electrode pad P is defined as wl _i and the diameter of the i-th probe 12A is defined as w2 _i , and the needle traces F of the electrode pad P and the probe 12A are respectively defined. They have their own sizes, some have different sizes, and some have the same size. When the size of the electrode pad P and the size of the needle trace F of the probe 12A are not necessarily the same, the contactable area S in the i-th electrode pad P is obtained using the following equations 4Ci and 4Di. Using the following formulas 4Ci and 4Di, the contactable regions S for all the electrode pads P are obtained from the following formulas 4C and 4D. Next, the same process as in the case where the contactable area S is obtained in the above expressions 4A and 4B is executed to execute the flowchart shown in FIG. 3.

C _min (i) = max (-w1 _i / 2 + w2 _i / 2, -w1 _i / 2 + w2 _i / 2 + x _i ). Expression 4 Ci

C _max (i) = min (w1 _i / 2-w2 _i / 2, w1 _i / 2-w2 _i / 2 + x _i )... Expression 4Di

C _min = max (C _min (1), C _min (2), C _min (3), ... C _min (n)). Formula 4C

C _max = min (C _max (1), C _max (2), C _max (3),… C _max (n))... Expression 4D

That is, by substituting the xy coordinate value of the center of the new needle Fn into Formula 4A and Formula 4B, as shown in FIG. 3, step S11 is performed and the several probe 12A after preheating in high temperature test is performed. The contactable area S can be calculated. After obtaining the contactable area S, it is determined in the central processing unit 15A whether or not the contactable area S is in the electrode pad P (step S12). When the contactable area S is in the electrode pad P, the plurality of probes 12A can reliably contact in all the electrode pads P, and the device D can be inspected. However, if at least part of the contactable region S protrudes from the electrode pad P, there will be a probe 12A protruding from the electrode pad P among the plurality of probes 12A, so that high temperature inspection cannot be performed. Is alerted by the function of the control device 15 (step S12A).

By the way, when the contactable area | region S contains the origin O of the electrode pad P, as shown to FIG. 7 (a), under the control of the control apparatus 15, the correction amount calculated | required based on the center of the spherical needle F is as it is. By moving the semiconductor wafer W to the contact position, the plurality of probes 12A at this time can be brought into contact with the center of the plurality of electrode pads P corresponding thereto. However, as shown in Fig. 7B, when the above-mentioned correction amount is used as it is when the contactable area S is out of the center of the electrode pad P, the probe 12A is moved out of the contactable area S. Correction is performed at the center, and any one of the plurality of probes 12A is out of the contactable area S and cannot perform high temperature inspection. Thus, in such a case, the plurality of probes 12A each are moved by adding the xy coordinate value of the contactable region S closest to the center of the electrode pad P to the correction amount as the offset amount to move the semiconductor wafer W. Can be brought into contact with the center of the plurality of electrode pads P corresponding thereto. In addition, when the contactable area S is not formed, or when the electrode pad is smaller than the predetermined size, it is not suitable as the correction amount, and a warning is given to the attention. This contactable area | region S can be used also in this high temperature test.

When contactable area | region S is formed in electrode pad P, this high temperature test can be performed and the correction amount used for the next high temperature test can also be calculated | required. Here, this correction amount is defined as a second correction amount. When the second correction amount is obtained in preparation for the next high temperature inspection, the second correction amount can be obtained by the same method as the correction amount based on the old needle trace F, using the new needle trace Fn formed in the current high temperature inspection. That is, first, the centers of the new needle marks Fn of the plurality of probes 12A are obtained, and then the second coordinate amounts are calculated by applying the center coordinates of these new needle marks Fn to the equations 3A and 3B.

The new needle trace Fn is formed in the vicinity of the old needle trace F, as shown in Fig. 5B. Since the new needle trace Fn shown in this figure does not overlap with the old needle trace F, the center of the new needle trace Fn can be obtained similarly to the old needle trace F. However, when the new needle Fn partially overlaps the old needle F, the center of the new needle Fn is unknown. In this case, for example, the technique described in Japanese Patent Laid-Open No. 2006-278381 proposed by the present applicant can be applied. Here, the case where the new needle trace Fn does not overlap the old needle trace F will be described.

However, even in the case shown in Fig. 5B, the old needle marks F and the new needle marks Fn cannot be distinguished. Therefore, in the present embodiment, the new needle using the binarized first image including the old needle track F captured in step S2 and the second binary image including both the old needle F and the new needle Fn. Only the local station Fn is extracted (step S13). That is, under the control of the control device 15, when the first and second second images are read from the image storage section 15E to the central processing unit 15A, and the difference between the first images is obtained from the second images, As shown by broken lines in Fig. 5C, the old needle marks F are lost, and only the new needle marks Fn are extracted. In this way, the center of the new needle trace Fn can be obtained based on the extracted image (hereinafter referred to as "extracted image"). The new needle Fn is obtained for all of the plurality of probes 12A.

Subsequently, as shown in FIG. 8A, the contact positions of the plurality of probes 12A with respect to the plurality of electrode pads P are determined based on the area S contactable with the second image and the correction amount obtained in step 5. FIG. The expected contact position Fs is applied when corrections are made to the center of the electrode pad P, respectively, and the center of the contact expected position Fs is within the contactable area S of the electrode pad P and the needle marks F and It is judged whether or not to enter the blank area without new needle trace Fn (step S14). When the extracted image can be arranged in the empty area within the contactable area S, the contact scheduled position Fs is disposed therein (step S15), and then the center of the contact scheduled position Fs at the position is determined (step S16). In the case where the center of the contact scheduled position Fs does not satisfy the above condition and is located in the empty region of the electrode pad P as shown in FIG. 8B, the center of the contact scheduled position Fs protrudes from the contactable region S. Since the probe 12A causing contact failure is contained and the high-temperature inspection cannot be executed, a warning is issued to alert attention (step S14A). As shown in FIG. 8C, when the center of the contact scheduled position Fs is in the contactable area S, but the contact scheduled position Fs cannot be disposed in the empty area, the existing needle trace F and the new needle trace The contact scheduled position Fs is arranged so that the overlap of Fn becomes the smallest. In this case, the contact scheduled position Fs may be set to call attention to the fact that it cannot be arranged in the empty area, and the contact scheduled position Fs may be arranged so as to minimize the overlap based on the call.

When the center of the contact scheduled position Fs is obtained as described above, these data are stored in the image storage unit 15E and stored in the image storage unit 15E. These data are used when performing the following high temperature test. In addition, when the next high temperature test is performed in another test apparatus, these data are transplanted into another test apparatus using a communication medium or a magnetic recording medium.

When the above operation is complete | finished, the inspection apparatus 10 performs index conveyance of the semiconductor wafer W by the mounting table 11 under control of the control apparatus 15, and performs high temperature inspection of this time. After the high temperature inspection of one semiconductor wafer W is completed, the subsequent semiconductor wafer W is mounted on the mounting table 11. Since this semiconductor wafer W is the same as the last semiconductor wafer W, alignment is abbreviate | omitted and high temperature inspection is performed by performing index transfer of the semiconductor wafer W. FIG.

As described above, according to the present embodiment, in this high temperature inspection, the plurality of electrode pads P of the semiconductor wafer W mounted on the mounting table 11 and the probe card 12 arranged above the mounting table 11 are provided. A plurality of probes 12A of (A) are electrically contacted to inspect electrical characteristics of the plurality of devices D in the semiconductor wafer W, and the needle marks F of the plurality of probes 12A formed on each of the plurality of electrode pads P are removed. And a step of correcting the contact positions of the plurality of electrode pads P and the plurality of probes 12A in preparation for the inspection, and a step of correcting the contact positions of the plurality of electrode pads P and the plurality of probes 12A. In order to detect the spherical needle F formed in each of the plurality of electrode pads P, a process of imaging the plurality of electrode pads P to obtain a first image, and using the first image, the center of each of the plurality of electrode pads P and these electrodes tile The process of obtaining the positional displacement amount of the center of each of the needle marks F in P, and the contact positions of the plurality of probe pads P used in the present inspection with respect to the plurality of electrode pads P A process of correcting each center of the plurality of electrode pads P using the center and respective positional displacement amounts, and a plurality of probes 12A and a plurality of electrode pads P used for the current inspection after the correction in this process. Contacting each other to form a new needle trace Fn, imaging a plurality of electrode pads P on which the new needle traces Fn are formed, respectively, and obtaining a second image; and sizes of the plurality of electrode pads P and respective electrode pads P In accordance with the center of the new needle trace Fn in the present invention, the contact pads S of the plurality of probes 12A are obtained in the respective electrode pads P. Even when the needle needle F is reliably detected by the CCD camera 13A, alignment of the plurality of probes 12 in the present inspection is performed to form a new needle trace Fn, and the new needle trace Fn is further formed. By using this method, the contactable regions S of the plurality of probes 12A are obtained, and the plurality of electrode pads P and the corresponding plurality of probes 12A are electrically and reliably contacted to reliably perform high temperature inspection with high reliability. .

Moreover, according to this embodiment, the process of correct | amending the contact position of the some electrode pad P and the some probe 12A compared with a test | inspection is carried out in order to detect the spherical needle F formed in each of the some electrode pad P, respectively. Imaging of the electrode pad P to obtain a first image, and using the first image, the position shift amount of the center of each of the plurality of electrode pads P and the center of each of the spherical needle marks F in these electrode pads P is determined. The contact position with respect to the some electrode pad P of the some probe P used for the test | inspection, and the present inspection is calculated | required, using the center of the some needle trace F, and the center position of the some electrode pad P, respectively. And a step of making a new needle trace Fn, respectively, by contacting the plurality of probes 12A and the plurality of electrode pads P used in the present inspection after the correction in this step, respectively. Imaging the plurality of electrode pads P having the marks Fn formed therein to obtain a second image, and comparing the first image and the second image to extract images of the new needle marks Fn of each of the plurality of electrode pads P; Using the position shift amounts of the centers of the electrode pads P and the centers of the new needle marks Fn in these electrode pads, the contact scheduled positions Fs to be contacted by the plurality of probes in the next inspection are obtained, and the plurality of contact schedules are obtained. Comparing the position Fs and the free area without the needle trace of the second image, and when the plurality of contact scheduled positions Fs are included in each blank area, placing the plurality of contact scheduled positions Fs in each blank area and obtaining the respective centers. And a step of correcting the contact position of each of the plurality of probes 12A with the center of the plurality of contact scheduled positions Fs arranged in each blank area. Even when the de P is miniaturized, by using the spherical needle F formed on the electrode pad P, the plurality of probes 12A are brought into contact with the empty regions of the respective electrode pads P in the next high temperature test, and the respective electrode pads P And high temperature inspection with high reliability can be performed.

Further, according to the present embodiment, when each of the plurality of contactable regions S is included in the plurality of electrode pads P, a step of obtaining the extracted image Fn of the new needle marks in the plurality of electrode pads P extracted from the first image and the second image. And the contact scheduled positions Fs to be contacted by the plurality of probes in the next inspection by using the displacement amounts of the centers of the plurality of electrode pads P and the centers of the new needle marks Fn in these electrode pads. Of the contact scheduled positions Fs of the plurality of electrode pads P and the blank regions within the contactable regions S of each of the plurality of electrode pads P and no needle marks, respectively, and when the plurality of scheduled contact positions Fs are included in each of the blank regions, Arranging contact scheduled positions Fs and obtaining respective centers; and a plurality of extracted images arranged in contact positions and empty regions of the plurality of probes 12A, respectively. Since the process of correcting to the center is provided, the plurality of probes 12A are reliably contacted by the empty areas of the respective electrode pads P in the next high temperature inspection, thereby preventing damage to the respective electrode pads P and The high temperature inspection with high reliability can be performed.

2nd Embodiment

In the present embodiment, an inspection method for efficiently bringing the probe 12A into contact in the empty region formed between the plurality of needle marks in the electrode pad P will be described with reference to FIGS. 9 to 13. The empty area means an area in the electrode pad P capable of contacting the probe 12A without overlapping the existing needle trace. When the existing needle traces are plural and the probe 12A cannot be contacted without overlapping with the existing needle traces, the optimum position of the contact scheduled position where the overlap with the existing needle traces is minimized is found. By minimizing the overlap with the existing needle traces, it is possible to prevent damage to the electrode pads and further damage to the device. A contact scheduled position can be calculated | required in the same procedure as 1st Embodiment. On the other hand, in Figs. 9 to 14, the circumferential quadrangle of the needle marks is shown instead of the needle marks.

There are two ways to find an empty area. The first method is a method for moving the probe 12A to the position closest to the contact scheduled position, where the overlap with the existing needle marks in the electrode pad is minimized. The second method maintains the positional relationship with the existing needle marks around the intended contact position, and then moves the probe to the position closest to the expected contact position, where the overlap with the existing needle marks in the electrode pad P is minimized. 12A).

For example, as shown in Fig. 9A, two existing spherical needle marks (indicated by the circumscribed rectangle of needle marks) F1 and F2 and one needle needle F2 in the electrode pad P are used. A new needle trace Fn obtained by correcting the contact position of the current probe 12A (indicated by the circumscribed square of the needle trace) Fn is formed, and the position shift amount between the center of the new needle trace Fn and the center of the electrode pad P is used. In the same manner as in the first embodiment, the position of the new needle trace Fn is corrected, and the estimated contact position (represented by the circumscribed square of the needle trace) Fs of the probe 12A in the following inspection is obtained. The contact scheduled position Fs partially overlaps the old needle station F2 and the new needle station Fn, as shown in FIG. Therefore, in this embodiment, the position where the overlap of the old needle trace F2 of the contact scheduled position Fs and the new needle trace Fn becomes the minimum is correct | amended as the optimal position Fc of the contact scheduled position Fs.

In the first method, the optimum position (position not overlapping with existing needle traces F1, F2, Fn) Fc is found in the entire electrode pad P as shown in FIG. The position is determined as the contact scheduled position Fa of the next inspection. In this case, the overlapped portion is zero. However, this method has a problem that the blank area decreases at once when the next inspection is executed.

In the second method, while maintaining the positional relationship between the old needle trace F2 and the new needle trace Fn, a blank area is obtained and the contact scheduled position Fs is corrected to the optimum position Fc. The overlap between the contact position Fs and the existing needle traces F2 and Fn is minimized to prevent damage to the electrode pad P. Also in the case of finding an empty area, it is preferable that the optimum position Fc is as close to the contact scheduled position Fs as possible. This is because, after the probe 12A has contacted the optimum position Fc, the contact position may be returned to the contact scheduled position Fs and may be in contact with another position. So, below, it demonstrates also with reference to FIGS. 10-13 about a 2nd method.

In order to obtain the optimum position Fc in the empty area from the contact scheduled position Fs, the contact scheduled position Fs corrected based on the position shift amount between the center of the existing new needle trace Fn and the center of the electrode pad P is, for example, shown in FIG. As shown to a) and (b), it overlaps with existing new needle trace Fn partially.

In this method, superimposition of the contact scheduled position Fs and the new needle Fn is examined in FIGS. 10A and 10B, and for example, which side of the scheduled contact position Fs overlaps the new needle Fn. do. Of the sides where the contact scheduled position Fs overlaps, the side with large overlap is defined as a target slice. In FIG. 10 (a), since the slice on the right side indicated by the thick line at the contact scheduled position Fs is larger than the slice on the upper side, the slice on the right side indicated by the thick line is the target slice. In (b) of the same figure, since the upper side fragment shown by the thick line of the contact plan position Fs is larger than the fragment of the right side, the fragment of the upper side shown by a thick line becomes a target fragment. In addition to those shown in Figs. 10A and 10B, there are types of target fragments shown in Figs. 11A to 11D, for example.

While maintaining the positional relationship between the contact scheduled position Fs and the new needle trace Fn, the contact scheduled position Fs is moved relative to the overlapping portion of the other side in the vertical direction of the target intercept in order to minimize or overlap the contact. Overlapping of the predetermined position Fs can be made minimum or zero. In the case shown in Fig. 10A, as shown in Fig. 12A, as shown in Fig. 12B, when the contact scheduled position Fs is moved by the overlap of the other side in the left direction, the overlap is zero. In the case shown in FIG. 10B, when the contact scheduled position Fs is moved downward by the overlap of the other side, the overlap becomes zero. The type of FIG. 11A includes the type of FIG. 10 and can be corrected to an optimal position based on the target intercept. In addition, even in the case of the type shown to FIG.11 (b), (c), since one target fragment is included, the contact plan position Fs can be corrected to an optimal position. However, in the case of the type shown in FIG. 11 (d), since there are a plurality of target fragments, the optimum position cannot be set. Therefore, in the case of the type of Fig. 11D, the correction to the optimum position is not performed.

9 (a) and 13, when the contact scheduled position Fs overlaps with both the old needle marks F2 and the new needle marks Fn, the contact scheduled positions Fs can be moved so that the overlap becomes zero. none. In this case, the contact predetermined position Fs is moved so that a target fragment may move to the vertical direction so that the left-right overlap may be equalized. Thus, by dividing the overlapping part equally to the left and right, damage in both needle traces can be reduced. In FIG. 13, the length of the target fragment of contact scheduled position Fs and the new needle trace Fn is ay, the length of another overlapping edge is ax, and the length of the target fragment of contact scheduled position Fs and needle stitch F2 is different by If the length of the side is bx, the movement amount x in the x direction can be obtained by the following equation.

SL (overlap area with old needle trace after movement) = (bx-x) X by

SR (overlap area with new needle trace after movement) = (ax + x) X ay

Here, x is obtained from the relationship of SL = SR.

(bx-x) × by = (ax + x) × ay

Therefore, the movement amount x = (bx by-ax a) / (ay + by).

In this way, after the amount of movement in the x direction is obtained, the amount of movement in the y direction is obtained in the same manner as the amount of movement in the x direction, and the contact scheduled position Fs is optimized.

Instead of the movement amount at which the overlap amount is equal to the left and right, the movement amount at which the sum of the left and right overlap areas is minimum and the overlapping width (ax and bx in FIG. 13) may be obtained.

In order to optimize the movement in the x direction as described above, a directed graph (hereinafter, referred to as a "contiguous relation graph") having a node having an existing needle trace and a contact scheduled position representing a neighboring relationship between existing values in advance is referred to. It is good to make the existing needle trace related to the contact scheduled position Fs from the adjacent relationship graph, and to obtain the evaluation amount, such as the overlap width with the existing needle trace.

When the contact scheduled position Fs overlaps with both the new needle marks Fn and the passivation edge as shown in Fig. 14, considering the side of the inner side by a predetermined distance from the passivation edge in the same manner as the existing needle trace circumscribed rectangle side, In this way, the contact scheduled position Fs can be moved to an optimal position between the new needle Fn and the passivation. In addition, when the condition to be separated from the passivation edge by a certain distance or more must be satisfied, after the condition is satisfied, the amount of movement that becomes as small as possible to overlap with the existing new needle trace Fn is obtained. 14, the outer side of a broken line is a passivation layer.

In addition, in this embodiment, when the contact scheduled position Fs is moved to the optimum position Fc, the method of obtaining the movement amount using the circumscribed rectangle of the needle trace was described, but the bit is made by using the binarization image representing the actual needle trace region The overlapping part may be calculated by a map operation.

As explained above, according to this embodiment, it is a process after having calculated | required the contact plan position Fs which several probe 12A contacts in the next test | inspection in the same procedure as 1st Embodiment, respectively, in each of the some plan scheduled position Fs. When the extracted images (circumscribed squares) Fn of the arranged plurality of needle traces overlap with the existing needle traces (circumscribed squares) F1, the target intercept of the position where the overlap is minimum, that is, the contact scheduled position Fs, in the vertical direction is Since the contact scheduled position Fs is moved to the shortest distance and the process of correcting the contact scheduled position Fs is provided, the contact scheduled position Fs is efficiently disposed in an empty area, thereby preventing damage to the existing needle marks F1 and Fn. In addition to being able to suppress, furthermore, damage to the device can be suppressed, the effect can be expected as in the first embodiment.

Third embodiment

In this embodiment, as shown in FIG. 15, a Voronoi degree is created about the center of the existing needle trace. In addition, in this embodiment, the needle trace is shown by the circumscribed rectangle of a needle trace similarly to 2nd Embodiment. Voronoi degree refers to the drawing of the area classified according to which parent point the point of the same distance space is close to the several points (parent point) arrange | positioned in the arbitrary position on arbitrary distance space. The boundary of an area becomes part of the bisector of the parent point of each area. As shown in Fig. 15A, the Voronoi boundary line L is located farthest from the center of the existing needle marks F1, F2, and Fn. As shown in Fig. 15B, the position closest to the Voronoi boundary L from the center of the contact scheduled position Fs obtained based on the new needle trace Fn becomes the optimum position Fc after optimization.

According to this embodiment, instead of arranging the contact scheduled position Fs of the probe 12 efficiently in the empty area using the external rectangles of the needle marks F1 and Fs in the second embodiment, the existing needle marks F1, By using the Voronoids of F2 and Fn, contact scheduled position Fs can be arrange | positioned efficiently, and the effect similar to 2nd Embodiment can be expected.

In addition, although the high temperature test | inspection of the to-be-tested object was demonstrated in the said embodiment, it is not limited to a high temperature test | inspection and can also apply to other various test | inspection similarly. This invention is not restrict | limited at all to the said embodiment, Each component can be changed suitably as needed.

INDUSTRIAL APPLICABILITY The present invention can be suitably used for an inspection apparatus that performs electrical property inspection of an inspection object such as a semiconductor wafer.

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows the structure of the test | inspection apparatus used for implementing one Embodiment of the method of this invention.

2 is a flowchart showing one embodiment of an inspection method of the present invention using the inspection apparatus shown in FIG.

3 is a flowchart showing a part of the flowchart shown in FIG. 1 in more detail.

4 (a) and 4 (b) are plan views showing the correction of the positional shift amount based on the needle traces of the probes in the electrode pads of the device, respectively (a) is a drawing of the spherical needle marks, and (b) Shows the needle traces of an ideal probe.

5A to 5C are plan views illustrating a process of extracting new needle marks from the needle marks on the electrode pads of the second image by using existing needle marks of the electrode pads of the first image, respectively.

Fig.6 (a), (b) is explanatory drawing explaining another embodiment of the test | inspection method of this invention, respectively.

7 (a) and 7 (b) are plan views showing the contactable regions of the probes in the electrode pads, respectively.

(A), (b), (c) are diagrams showing the relationship between the contactable regions of the probes in the electrode pads and the arrangement regions of the probes assigned in the following inspection, respectively.

9 (a) to 9 (c) are plan views for explaining a method of optimally arranging a predetermined contact position of a probe in an empty area of an electrode pad, respectively.

10 (a) and 10 (b) are plan views illustrating the overlapping state of the contact scheduled positions of the probes and the existing needle marks, respectively;

11 (a) to 11 (d) are plan views illustrating the overlapping state of the contact scheduled position of the probe and the existing needle marks, respectively.

12 (a) and 12 (b) are plan views for explaining a method of correcting by moving a predetermined contact position of a probe to an optimum position, respectively.

FIG. 13 is a plan view for explaining in detail a method of correcting by moving a predetermined contact position of a probe to an optimal position; FIG.

14 is a plan view for explaining a method of correcting a contact scheduled position by moving to a optimum position when the contact scheduled position of the probe is caught by the passivation layer;

15 (a) and 15 (b) are plan views for explaining another method of correcting by moving a predetermined contact position of a probe to an optimal position, respectively.

(Explanation of symbols for the main parts of the drawing)

10 inspection device 11 mount

12 probe card 12A probe

13A CCD Camera 15 Controller (Computer)

15A Central Processing Unit D Device

F Needle Needle Fn New Needle Trace

Fs contact position P electrode pad

W semiconductor wafer (inspection)

Claims (9)

In a test method in which the plurality of electrode pads of a test target mounted on a mounting target and a plurality of probes of a probe card arranged above the mounting table are electrically contacted, an inspection of the electrical characteristics of the test target is performed. Using a needle trace of the plurality of probes formed on each of the plurality of electrode pads in the inspection, correcting a contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection; The process of correcting the contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, A first process of imaging the plurality of electrode pads to obtain a first image to detect the needle marks formed on each of the plurality of electrode pads; A second step of calculating the positional displacement amount of the center of each of the plurality of electrode pads and the center of gravity of each of the needle marks in these electrode pads using the first image; A third for correcting each contact position of the plurality of probes used for the inspection with respect to the plurality of electrodes at the centers of the plurality of electrode pads by using the positions of the plurality of needle marks and the respective positional displacement amounts, respectively; Fair, A fourth step of contacting the plurality of probes used for the inspection with the plurality of electrode pads after correction in the third step to form new needle marks on the plurality of electrode pads, respectively; A fifth process of imaging a plurality of electrode pads each having the new needle marks formed thereon to obtain a second image; And a sixth step of obtaining a contactable region of each of the plurality of probes in each of the electrode pads based on the sizes of the plurality of electrode pads and the center of a new needle mark in each of the electrode pads. method of inspection. In a test method in which the plurality of electrode pads of a test target mounted on a mounting target and a plurality of probes of a probe card arranged above the mounting table are electrically contacted, an inspection of the electrical characteristics of the test target is performed. Using a needle trace of the plurality of probes formed on each of the plurality of electrode pads in the inspection, correcting a contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection; The process of correcting the contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, A first process of imaging the plurality of electrode pads to obtain a first image to detect the needle marks formed on each of the plurality of electrode pads; A second step of calculating the positional displacement amount of the center of each of the plurality of electrode pads and the center of gravity of each of the needle marks in these electrode pads using the first image; A third for correcting each contact position of the plurality of probes used for the inspection with respect to the plurality of electrodes at the centers of the plurality of electrode pads by using the positions of the plurality of needle marks and the respective positional displacement amounts, respectively; Fair, A fourth step of contacting the plurality of probes used for the inspection with the plurality of electrode pads after correction in the third step to form new needle marks on the plurality of electrode pads, respectively; A fifth process of imaging a plurality of electrode pads each having the new needle marks formed thereon to obtain a second image; The first image and the second image are compared to extract images of new needle marks of each of the plurality of electrode pads, and the centers of the plurality of electrode pads and each of the new needle marks in these electrode pads are extracted. The positional displacement amount of the center is obtained, and the positional displacement amount is used to find the contact position to be contacted by the plurality of probes in the next inspection, and the contact position is compared with the blank area free of needle marks in the second image. A sixth step of arranging the contact scheduled positions in the respective blank areas and obtaining respective centers of gravity when the contact scheduled positions are included in the respective blank areas; And a seventh step of correcting the contact position of each of the plurality of probes with the center of the contact scheduled position arranged in the respective blank areas. In a test method in which the plurality of electrode pads of a test target mounted on a mounting target and a plurality of probes of a probe card arranged above the mounting table are electrically contacted, an inspection of the electrical characteristics of the test target is performed. Using a needle trace of the plurality of probes formed on each of the plurality of electrode pads in the inspection, correcting a contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection; The process of correcting the contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, A first process of imaging the plurality of electrode pads to obtain a first image to detect the needle marks formed on each of the plurality of electrode pads; A second step of obtaining a position shift amount between a center of each of the plurality of electrode pads and a center of each of the needle marks in these electrode pads using the first image; A third for correcting each contact position of the plurality of probes used for the inspection with respect to the plurality of electrodes at the centers of the plurality of electrode pads by using the positions of the plurality of needle marks and the respective positional displacement amounts, respectively; Fair, A fourth step of contacting the plurality of probes used for the inspection with the plurality of electrode pads after correction in the third step to form new needle marks on the plurality of electrode pads, respectively; A fifth process of imaging a plurality of electrode pads each having the new needle marks formed thereon to obtain a second image; A sixth step of obtaining a contactable region of each of the plurality of probes in each of the electrode pads based on the sizes of the plurality of electrode pads and the center of a new needle mark in each electrode pad; A seventh step of determining whether each of the plurality of contactable regions is each included in the plurality of electrode pads of the second image, and An eighth step of extracting images of new needle marks in the plurality of electrode pads based on the first image and the second image when each of the plurality of contactable regions is included in the plurality of electrode pads; The position shift amount of the center of each of the said plurality of electrode pads, and the center of each said new needle trace in these electrode pads is calculated | required, and this position shift amount is used for the contact which the said some probe will contact at the next test | inspection. A position is obtained, and the contact scheduled position is compared with a blank area without needle marks in each of the contactable areas of each of the plurality of electrode pads, and when the contact scheduled position is included in each of the blank areas, the contact within the respective blank areas. And a ninth step of arranging a predetermined position and finding each center as a contact position of each of the plurality of probes. In a test method in which the plurality of electrode pads of a test target mounted on a mounting target and a plurality of probes of a probe card arranged above the mounting table are electrically contacted, an inspection of the electrical characteristics of the test target is performed. Using a needle trace of the plurality of probes formed on each of the plurality of electrode pads in the inspection, correcting a contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection; The process of correcting the contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, A first process of imaging the plurality of electrode pads to obtain a first image to detect the needle marks formed on each of the plurality of electrode pads; A second step of calculating the positional displacement amount of the center of each of the plurality of electrode pads and the center of gravity of each of the needle marks in these electrode pads using the first image; A third for correcting each contact position of the plurality of probes used for the inspection with respect to the plurality of electrodes at the centers of the plurality of electrode pads by using the positions of the plurality of needle marks and the respective positional displacement amounts, respectively; Fair, A fourth step of contacting the plurality of probes used for the inspection with the plurality of electrode pads after correction in the third step to form new needle marks on the plurality of electrode pads, respectively; A fifth process of imaging a plurality of electrode pads each having the new needle marks formed thereon to obtain a second image; The images of the plurality of new needle marks are extracted by comparing the first image and the second image, respectively, and based on the centers of the plurality of extracted images and the centers of the respective electrode pads, the first to the second images are extracted. A sixth step of obtaining the contact positions to be contacted by the plurality of probes in the next inspection in the same procedure as in the third step, When the plurality of extracted images respectively disposed at the plurality of contact scheduled positions overlap each other with existing needle marks, the respective contact scheduled positions are moved to the shortest distance at the position where the overlap is minimum, and the An inspection method comprising the seventh step of performing correction. In a test method in which the plurality of electrode pads of a test target mounted on a mounting target and a plurality of probes of a probe card arranged above the mounting table are electrically contacted, an inspection of the electrical characteristics of the test target is performed. Using a needle trace of the plurality of probes formed on each of the plurality of electrode pads in the inspection, correcting a contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection; The process of correcting the contact position of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, A first process of imaging the plurality of electrode pads to obtain a first image to detect the needle marks formed on each of the plurality of electrode pads; A second step of calculating the positional displacement amount of the center of each of the plurality of electrode pads and the center of gravity of each of the needle marks in these electrode pads using the first image; A third for correcting each contact position of the plurality of probes used for the inspection with respect to the plurality of electrodes at the centers of the plurality of electrode pads by using the positions of the plurality of needle marks and the respective positional displacement amounts, respectively; Fair, A fourth step of contacting the plurality of probes used for the inspection with the plurality of electrode pads after correction in the third step to form new needle marks on the plurality of electrode pads, respectively; A fifth process of imaging a plurality of electrode pads each having the new needle marks formed thereon to obtain a second image; The images of the plurality of new needle marks are extracted by comparing the first image and the second image, respectively, and based on the centers of the plurality of extracted images and the centers of the respective electrode pads, the first to the second images are extracted. A sixth step of obtaining the contact positions to be contacted by the plurality of probes in the next inspection in the same procedure as in the third step, In each of the plurality of electrode pads of the second image, a Voronoi DIAGRAM is created based on the existing plurality of needle marks, and the center of each of the extracted images arranged at the plurality of contact scheduled positions. And a seventh step (C) of correcting each of the contact positions, respectively, by moving the shortest distance up to the nearest Voronoi boundary line. The method according to any one of claims 1 to 5, And said new needle trace is formed by using a test subject previously set at a predetermined temperature. The method according to any one of claims 1 to 5, The position shift amount obtained in the said 2nd process is calculated | required by the least square method using the center of the said electrode pad and the center of the said needle trace formed in each of the said some electrode. The method according to claim 1 or 3, The range of the x coordinate value of the contactable area | region obtained at the said 6th process makes the origin of the center of the said some electrode pad, and the width of the new needle trace in the x coordinate value of the edge of the negative side of the said electrode pad. The larger of the correction x coordinate value obtained by adding half of and the x coordinate value of the center position of the new needle trace having the maximum x coordinate value to this correction x coordinate value is obtained as the minimum x coordinate, The smaller one of the sum of the x-coordinate value of the edge of the positive side of the electrode pad and the x-coordinate value of the center position of the new needle trace having the minimum x-coordinate value is obtained as the maximum x-coordinate. And the range of the y coordinate of the contactable area is determined in the same manner as the range of the x coordinate value. An inspection method in which a computer is driven to electrically contact a plurality of electrode pads of an inspected object mounted on a mounting object with a plurality of probes of a probe card disposed above the mount, and thereby inspect the electrical characteristics of the inspected object. And correcting the contact positions of the plurality of electrode pads and the plurality of probes in preparation for the current inspection, using needle marks of the plurality of probes formed on each of the plurality of electrode pads in a previous inspection. A program recording medium that records a program for executing an inspection method, When correcting the contact positions of the plurality of electrode pads and the plurality of probes using the needle marks, the program drives the computer to execute the inspection method according to any one of claims 1 to 5. A program recording medium.

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